The object of this project is the elucidation of the biochemical mechanism of compensatory skeletal muscle hypertrophy. These studies will give greater insight into the physiological regulation of normal and pathologic skeletal muscle metabolism and into the role of the nervous system in this regulation. Present topics of investigation include: 1) The relationship between compensatory skeletal muscle hypertrophy and endurance training; 2) the relationship between skeletal muscle and connective tissue in hypertrophy; 3) the relationship between stretch-induced hypertrophy and muscle protein synthesis and degradation; 4) localization of phosphoinositide changes in hypertrophy; and 5) cyclic nucleotide changes in hypertrophy.